Computing device



G. D. JOHNSON.

COMPUTING DEVICE.

APPLlcATIoN FILED MAR.\,1920.

Patented Feb. 7, 1922.

m. wkn JO D. G.

Br Y@ .17m/Mfrs UNITED STATES PATENT OFFICE.

GEORGE DAVID JOHNSON, OF CHICAGO, ILLINOIS; LOUISE JOHNSON ADHINISTRA- 'IRIX 0F SAID GEORGE DAVID JOHNSON, DECEASED.

COHPUTING DEVICE.

1,405,847. speomuonofmnhenn ,Patented Feb. 7', l1922. Application ma :man 1, im. seml no. ssasie.

To all whom it may concern: the center of the base A. A scale f is ar- Be it known that I, GEORGE D. JOHNSON, a citizen of the United States, and a resident of Chicago, in the county of Cook and State of Illinois, have invented a new and useful Im rovement in Computing Devices, of which tlli description.

My invention relates to improvements in devices for computing weight per square foot of leather belting, and it consists in the combinations, constructions, and arrangements herein described and claimed.

An object. of my invention is to provide a mechanical device comprising parts bearing scales having certain relations so that by set ting certain parts at certain relative positions the weight per square foot of leather belting in a roll in decimal ounces, the total weight of the roll being known is indicated upon the device without the necessity ofthe use of additional calculating instruments and without mathematical computation.

A further ob]` ect of my invention is to provide a device that is simple in Operation and which takes up relatively little space so that it may be readily carried about and utilized in places where 1t would be impossible or at least burdensome to carry linstruments of a morel complex nature.

Other Objects and advantages will appear in the following specification, and the novel features of the invention will be particularly pointed out in the appended claims.

My,invention is lllustrated in the accompanying drawings, forming part of this application, in which-v Fig. l is a face view of the device,

Fig. 2 is a sectional view of a part of the device along the line 2 2 of Fig. l.

In carrying out my invention, I provide a circular base A having a scale b circularly arranged around its outer edge. The unit of the scale b, which ranges from 40 to 399 inclusive, is l which is both the unit of length of a roll of belt in feet and the unit of total weight of a roll of belt in pounds. Fractions of units in the scale b are denoted by spaced graduations c between the lines denoting the multiples of the unit.

The title of the scale b namely: length (feet) and weight (pounds is marked upon the base A as indicated in Fig. l of the accompan ing drawings A dis D is concentrically mounted to rotate around the pivot E whlch projects from e following is a full, clear, and exact l ranged around the outer edge of the disk D and ranges from 1 to 9i inclusive, the unit being i of a linear inch. The scale f denotes the width of belt in inches. A scale g is concentrically arranged immediately within the scale f and ranges from 10 to 96, the unit being 1 inch, and the scale also denoting the width of belt in inches. he scales f and are marked as denoting the width of the be t in inches upon the face of the disk D, as

.shown in Fig. 1 of the accompanying drawings.

A circle H is the dividin line between the scale p and an inner scale c which is concentrical arranged with respect to the scales g and f. The scale i ranges from 10 to 50 inclusive and its unit is l decimal ounce. The scale i is indicated by the descriptive title weight per suare foot in decimal ounces upon the disk as shown in Fig. 1 of the accompanying drawings.

The title of the device and instructions for finding directions to operate the-device may be marked upon the space around the central part of the disk D. An indicator arm J,

which is a segment of a circle having the i same radius as the circular disk D, is mounted to rotate upon the pivot E. A knurled nut K screws upon thethreaded end of the pivot E to hold the indicator arm in a desired position with respect to the disk D and base A and also holds the disk D inia desired position with-respect to the base A` The indicator arm J has an aperture L positioned as indicated in Fig. l of the accompanying drawings. It will 'be noted that this arrangement presents the figures of the scale i to view, while the figures of the graduations of the scales f and g are'concealed beneath the end of the indicator arm J. An arrow ln. points inwardly to the scale z', while a simila-r arrow m points' outwardly toward the` total length and a given total weight, it is Wel only neceary lto turn the disk D until a figure in the scales f or g denoting the width of the belting registers with a figure in the scales b denoting the total length in feet of the roll. The total weight of the roll is also'` known and the indicator arm J is turned until the arrow m pointsto the total weight of the roll which is known. The arrow n will then'point to a figure in the scale i which will be the weight per square foot of the belt in decimal ounces. For example, suppose it is desired to ascertain the ht per square foot of single leather beltlng 22 inches wide in a roll 168% feet long. The total weight of the roll is known to e 411,1 pounds. scale f is placed in registration with 168% of the scale 'b'. The indicator arm is now turned until the arrow m points to 4M also in the scale b, since the scale b indicates both length in feet and weight in pounds. The arrow fn will indicate the number in the scale z' which is the weight per square foot of the belt in decimal ounces and is found to be 17.1.

The computer provides a means whereby the weight per square foot in decimal ounces of single or double leather belt in any width up to 100 inches may be' quickly and accurately determined without mathematical calculation. It is as simple an operation with the device to ure the weight per square foot of one mil ion feet weighing one million pounds as it would be to figure a length of one foot'weighing one pound. j

The scale b ran es from 40 to 399 inclusive but by using mutiples of the unit of the scale b any required length and weight' can be figured. Leather belting is put up and manufactured in rolls of varying lengths. The total length of the belting in each roll and the weight of the roll is known. The leather belting is sold by weight. 'It has heretofore been nece'ary to calculate mathematically the weight Vpier square foot. For example, to ascertain e weight per square foot of single belting 252 inches wide in a roll of 168% feet long, it would be necessary to multiply 168% by 2% and then divide the product -by 12 in order to determine the number of square feet in the roll. It would then be necessary to divide the weight of the total, which is known to be 4141 pounds by the result obtained in order to determine the weight per s uare foot in pounds and it would further e necessary to reduce. the product last obtained to ascertainthe welght per square foot in decimal ounces, which 1s the unit commonly employed in the sale of leather beltin It will be ovi'ous that considerable labor is required in computing the weight per The ligure 22 of thel square foot in decimal ounces, since the output of a factory will comprise a large number of rolls ofleath'er daily. There is also always the possibility of error when the results are determined by mathematical calculation. The employment of the device will therefore result in a reat saving of both time and money andg an accurate result will be obtained in every instance.

It will be observed that fractions of the unit of the scale are indicated by spaced graduations in order to permit results to be obtained with more exactness. v

I claim:

l. A calculating device comprising a circular base having a circular scale delineated thereon, about its outer edge, a second circular disk concentrically and rotatively mounted upon said circular base and having a diameter equal to that of the inner diameter of said first named circular scale, said second named circular disk having a scale delineated thereon about its outer edge and having an inner circular scale `delineated. thereon and spaced from the scale about its outer edge, said scales having graduations arranged for registry, and an indicator arm mounted for rotation about the common axis of said circular base and said circular diskand being arranged to indicate radially registering graduations representing correlated values in said irstnamed scale and said last named scale and to cover the intervenin segmental portion of the second name scale.

2. AA calculating device comprising a circular base having a circular scale delineated thereon about its outer edge, a second circuvmounted for rotation about the common axis of said circular base and circular disk, said indicator arm being a segment of a circle having the same radius as the second named circular disk and being formed with an aperture therethrough spaced from the outer end thereof to. uncover during a complete revolution thereof the last' named scale, and to simultaneously cover the second named scale, said indicator arm also being provided with an index at its outer end for indicating a selected graduation in the scaleon the circular base and with a radially alined index for indicating a result in the inner scale on the second named disk.

GEORGE DAVID JOHNSON. 

